Immobilizer system-mounting vehicle and member used for the immobilizer system

ABSTRACT

An operation member containing a transmitter for an immobilizer or receiver for the immobilizer, is indicated to a user so that the user may carefully handle the operation menber. An ignition key ( 1 ) has a grip ( 3 ) and a key plate ( 2 ) protruding from the grip ( 3 ). “Immobi” is engraved on the surface of the grip ( 3 ) to thereby form a first indication portion ( 11 ). “Immobi” is an abbreviation for an English word “immobilize”. Inside the grip ( 3 ) is contained a transponder which is an immobilizer transmitter.

BACKGROUND OF THE INVENTION

The present invention relates to immobilizer systems for installation invehicles, immobilizer operation members incorporating immobilizertransmitters for transmitting immobilizer identification codes, andimmobilizer operation member receiving devices for receiving theimmobilizer operation members.

Automobile engines are started by inserting an ignition key into a keycylinder and turning it.

In recent years, to prevent thefts, ignition keys that control enginestarting with electric signals, which are transmitted from the key, inaddition to key turning have been used.

Such an ignition key incorporates a transmitter that transmits a specialidentification code (immobilizer identification code). When theidentification code transmitted from the transmitter matches anidentification code preset in an engine starting control computer (i.e.,ECU) of a receiver installed in the vehicle, the engine iselectronically controlled and started. Therefore, the starting of theengine is permitted only by a key incorporating the transmitter. Thisprevents the automobile from being stolen. Such a system is referred toas an immobilzer system.

The transmitter, which is incorporated in the ignition key, is driven bya battery, which is located in the grip of the key, to transmit anidentification code when a switch located on the grip is operated.However, the identification code cannot be transmitted when the batterybecomes low on power. In such case, the engine cannot be started evenwhen using an authorized ignition key. Thus, ignition keys incorporatingimmobilizer transmitters (hereafter referred to as transponders) that donot require batteries have recently become popular.

When magnetism produced by a magnetism generator of the receiver reachesthe transponder, the transponder converts the magnetic energy toelectric energy to generate electric power. The electric power is usedto transmit the radio waves of the identification code. This eliminatesthe need to replace batteries and enables usage over a long period oftime.

Generally, if a duplicate of the ignition key incorporating theimmobilizer transmitter is necessary, the duplicate must be bought fromthe dealer who sold the automobile.

However, in the prior art, the surface of the ignition key only includesmarkings such as the trademark of the automobile maker. Thus, if theuser forgets that the ignition key incorporates an immobilizertransmitter, the user may have a locksmith produce a duplicate that onlycopies the shape of the ignition key plate.

Although such a duplicate key has a key plate that is identical to thatof the ignition key, the duplicate key does not incorporate theimmobilizer transmitter. Accordingly, if the duplicate key is insertedinto the key cylinder and turned to start the engine, the engine willnot start. Furthermore, if a number of people use the same ignition key,some of them may not know about the immobilizer system. In such case,the ignition key may be handled carelessly, in the same manner as anormal ignition key that does not incorporate an immobilizertransmitter.

Additionally, in this system, it may be difficult to determine whetherthere is a problem with the vehicle or the immobilizer transmitter inthe ignition key when the engine does not start. In the prior art, thereis no way to recognize that the ignition key is one element of theimmobilizer system. Thus, if efforts to locate the cause of the problemare directed only toward the vehicle, troubleshooting of the ignitionkey will be delayed.

SUMMARY OF THE INVENTION

Accordingly, it is an objective of the present invention to provide avehicle having an immobilizer system installed, an immobilizer operationmember incorporating elements constituting the immobilizer system, and avehicle immobilizer operation member receiving device for receiving theimmobilizer operation member that indicates and notifies the user of theexistence of the immobilizer system so that the user will handle theimmobilizer operation member with care. It is also an objective of thepresent invention to provide a vehicle having an immobilizer system, animmobilizer operation member, and an immobilizer operation memberreceiving device that do not delay troubleshooting of the system.

The gist of the invention is an immobilizer system for installation in avehicle to prevent unauthorized use of the vehicle. The immobilizersystem includes a receiver attached to the vehicle, and a controlcircuit in the vehicle for storing an identification code. The controlcircuit is linked with the receiver. The system also includes anoperation member, which is independent and separable from the vehicle.The operation member stores a code. The operation member activates theimmobilzer system to perform a verification process for verifyingwhether the operation member is authorized for use with the vehicle whenthe operation member is placed in a predetermined position with respectto the vehicle. The system further includes a transmitter in theoperation member for transmitting a signal to the receiver forcommunication with the receiver regarding a comparison of the codestored in the operation member with the code stored in the vehicle.Operation of the vehicle is permitted only when the code stored in theactivator matches the code stored in the vehicle. The system furtherincludes an indication portion located on the operation member or thevehicle for indicating the existence of the immobilizer system. Theindication portion is capable of being noticed by a vehicle operator.

In one embodiment, the indication portion is a first indication portionlocated on the activator, and a second indication portion, which alsoindicates the existence of the immobilizer system, is located on asurface of the vehicle that is visible to the operator.

In a further embodiment, the activator is a key that is engagable with akey opening formed in the vehicle, and the first indication portion is asymbol located on the key.

Further, the first and second indication portions may be symbols thatare substantially the same.

In another embodiment, the indication portion is a symbol located on thevehicle in close proximity to the opening.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an ignition key employed in a first embodimentaccording to the present invention.

FIG. 2(a) is a cross-sectional plan view of the ignition key, and FIG.2(b) is a cross-sectional side view of the ignition key.

FIG. 3 is a perspective view showing a key cylinder.

FIG. 4 is a front view of a key cylinder employed in a secondembodiment.

FIG. 5 is a plan view showing a further embodiment.

FIGS. 6(a) to (f) are plan views showing further embodiments.

FIG. 7 is a plan view showing a further embodiment.

FIG. 8 is a plan view showing a further embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An ignition key serving as an immobilizer operation member according toa first embodiment of the present invention will now be described withreference to FIGS. 1 to 3.

As shown in FIG. 2(a), an ignition key 1 includes a key plate 2. The keyplate 2 has a base 2 a in which a cutaway portion 2 b is inclined at apredetermined angle (45° in the preferred embodiment) relative to thelongitudinal direction (horizontal direction as viewed in FIG. 1) of thekey plate 2. An engaging hole 2 c is formed in the base 2 a. Theignition key 1 further includes a grip 3.

As shown in FIGS. 2(a) and (b), the grip 3 includes a holder 4 and aprotector 5 covering the holder 4. The holder 4 is made of a highlyrigid resin or the like, such as polybutylene terephthalate (PBT), andis insert molded such that the base 2 a of the key plate 2 is covered.Insert molding refers to a method of molding in which a component madeof metal or other material, which is to be embedded in the moldedproduct, is arranged in a mold before starting the molding. In otherwords, the key plate 2 is arranged in a mold so that it is embedded inthe holder 4, which is the molded material, when molding is completed.

The protector 5 is made of a soft resin or the like, such as polyvinylchloride (PVC) and is also formed by insert molding such that the holder4 is covered. As shown in FIG. 1, “Immobi” is impressed on the surfaceof the protector 5 to define a first indication portion 11. “Immobi” isshort for immobilize, which means “render incapable of movement”. Theimpressed first indication portion 11 defines ridges and valleys on thesurface of the protector 5.

An accommodating cavity 6, which serves as an accommodating portion, isdefined in the holder 4. The accommodating cavity 6 extends parallel tothe cutaway portion 2 b of the key plate 2 and is inclined 45° withrespect to the longitudinal direction of the key plate 2. Theaccommodating cavity 6 has an opening 6 a facing toward the distal endof the ignition key 1 (toward the right as viewed in FIG. 1). Atransponder 7, which serves as an immobilizer transmitter, isaccommodated in the accommodating cavity 6.

The transponder 7 is a cylindrical glass tube containing an antennacoil, a transformer, a capacitor, an IC, and the like (none of which areshown) and has sealed semi-spherical ends.

The antennal coil is arranged in the transponder 7 generally in thelongitudinal direction of the transponder 7.

With the ignition key 1 inserted in the key cylinder, the antenna coilconverts the magnetism acting thereon to electric power most efficientlywhen arranged parallel to the key plate 2. Furthermore, the antenna coilconverts the magnetism acting thereon efficiently as long as the antennacoil is inclined about 45° or less with respect to the longitudinal axisof the key plate 2.

If the transponder 7 is arranged such that the antenna coil is parallelto the key plate 2, the long transponder 7 would make it necessary toextend the length of the grip 7. This arrangement would thus limit thelength of the transponder 7. However, if the transponder 7 is inclined45° with respect to the key plate 2, not only can magnetism beefficiently converted to electric power, but the grip 3 can also beshortened.

Furthermore, the transponder 7 must be separated from the metal base 2 aby a predetermined distance (about a few millimeters) to transmit radiowaves to the receiver without interference from the base 2 a. Thus, theaccommodating cavity 6 is formed such that the transponder 7 isseparated from the cutaway portion 2 b by a predetermined distance(about a few millimeters), and the transponder 7 is longitudinallyparallel to the cutaway portion 2 b of the key plate 2 when in theaccommodating cavity 6.

The accommodating cavity 6 is filled with a predetermined amount of anadhesive 8 before the transponder 7 is inserted. Thus, the adhesive 8fills the space between the transponder 7 and the wall of theaccommodating cavity 6. In this embodiment, silicone is employed as theadhesive 8.

A cap 9, which serves as a closing member, is fitted in the opening 6 ato close the accommodating cavity 6. The amount of adhesive 8 that fillsthe accommodating cavity 6 is predetermined such that when thetransponder 7 is inserted in the accommodating cavity 6, the adhesive 8sufficiently fills the space formed between the transponder 7, theaccommodating cavity 6, and the cap 9.

The immobilizer system of this embodiment will now be described.

The immobilizer system of this embodiment is shown in FIG. 3. Theimmobilizer system is constituted by the transponder 7 in the holder 4of the key 1, a transceiver circuit 24 serving as an immobilizerreceiver for performing code communication with the transponder 7 bymeans of an antenna coil 20, which is wound about a key cylinder 23 intowhich the key 1 is inserted, and a control circuit 25 for controllingthe operation of the transceiver circuit 24.

When antenna coil in the grip 3 generates electric current by receivinga magnetic field BD from the antenna coil 20 in the key cylinder, thetransponder 7 accumulate the electric current in the capacitor via thetransformer. When the accumulated voltage reaches a predetermined value,the transponder 7 transmits a predetermined identification code, whichis preset in the transponder's IC. As shown in the drawing, when thedriver inserts the key 1 into the key cylinder 23, the control circuit25 recognizes the insertion of the key 1 through a key unlock warningswitch (key existence switch) 22 and starts to read the identificationcode.

As described above, the transceiver circuit 24 supplies the transponder7 of the key 1 with electric power, which is generated byelectromagnetic coupling. This inputs the identification code, which isread from an control circuit 25 (not shown) of the transponder 7, intothe transceiver circuit 24. The transceiver circuit 24 demodulates theinput identification code in a predetermined manner and outputs the codeto the control circuit 25. The identification code reading process isconducted during the time period starting from when the key 1 isinserted to when the key 1 is turned to the starting position (usingabout 100 ms (milliseconds) of this time period).

After reading the identification code, the control circuit 25 comparesthe read identification code with a code registered in the EEPROM anddetermines whether the codes match.

If the identification codes do not match due to forgery of the key 1 orother reasons, the control circuit 25 sends a command code to an enginecontroller 26 to prohibit starting of the engine. As a result, theengine controller 26 prohibits the actuation of the ignitor, theinjector, or the fuel pump.

On the other hand, if it is determined that the identification codesmatch, the control circuit 25 sends a command signal to the enginecontroller 26 to permit starting of the engine (the issuance of startingpermission).

The issuance of the starting permission commences the controlling of theignitor, the injector, and the fuel pump with the engine controller 26and allows the vehicle to be driven. For the issuance of the startingpermission, other conditions must be satisfied. Such conditionsgenerally include the door being closed, the key unlock warning switch22 recognizing the key, and the ignition switch 21 being arranged at anIG-ON position (FIG. 3).

There are various electronic control methods that can be employed by acomputer to stop the starting of an engine. For example, if theidentification codes do not match, the of the ignition coil may be cut,the injection of fuel by an EFI (electronic fuel injection controller)may be cut, or the actuation of the starter may be prohibited. Themagnetism generator is actuated when the ignition key 1 is inserted intothe key cylinder.

The advantages of the above embodiment will now be described.

(A) To start the engine using the ignition key 1, which is describedabove, the ignition key 1 is inserted into the key cylinder and thenturned. When turning the ignition key 1, a force is applied to the grip3 in the torsional direction. However, the holder 4 of the grip 3 ismade of a resin having high rigidity. Thus, the grip 3 is not deformeddespite applications of torsional forces. Accordingly, the key plate 2does not become loose even if the ignition key 1 is turned repetitivelyand used over a long period of time.

(B) The magnetism generator of the key cylinder generates magnetism whenthe ignition key 1 is inserted into the key cylinder. The magnetismcauses the transponder 7 to generate electric current with the antennacoil in the transponder 7, which results in an accumulation of voltagein the capacitor via the transformer. Transmission of the predeterminedidentification code stored in the transponder's IC occurs when thevoltage accumulated in the capacitor reaches a predetermined value. Theantenna coil extends generally in the travelling direction of theignition key 1 so that the antenna coil magnetizes easily. Thus,electric power for transmitting the identification code is obtainedefficiently. Furthermore, the transponder 7 and the metal base 2 a areseparated from each other by a predetermined distance (a fewmillimeters) such that the transmitted radio waves are not interferedwith by the metal key plate 2. This guarantees the reception of theidentification code by the receiver in the key cylinder.

The identification code received by the receiver is compared with theidentification code stored in the engine starting control computer (ECU,or the like). When turning the ignition key 1, the engine is startedonly if the identification codes match. If the identification codes dono match, the computer prohibits the starting of the engine inaccordance with its controlling method, such as by cutting theactivation of the ignition coil, the injection of fuel with the EFI, orthe actuation of the starter. This prevents thefts.

(C) The protector 5 is made of a soft resin such as PVC. Therefore, thegrip 3 has a comfortable feel. Furthermore, if the ignition key 1 isdropped accidentally, the impact of the fall is absorbed by theprotector 5, which is made of a soft resin, and the adhesive 8, whichfills the accommodating cavity 6. This prevents damage to thetransponder 7.

(D) In this embodiment, the first indication portion 11 indicating“Immobi” is impressed on the surface of the protector 5, whichconstitutes the grip 3. This notifies the person holding the ignitionkey 1 that the key is special and contains electronic components. Thus,the person would likely know that the ignition key 1 must be handledwith care.

(E) The first indication portion 11 impressed on the surface of theprotector 5 has ridges and valleys. Thus, the first indication portion11 serves to prevent slippage.

(Second Embodiment)

A second embodiment will now be described with reference to FIGS. 3 and4.

FIG. 4 shows a schematic front view of a key cylinder 23, which servesas a receiving device located in front of the driver's seat.

In addition to the structure of the first embodiment, in thisembodiment, as shown in the drawing, a second indication portion 30 isimpressed on the key receiving surface of the key cylinder 23, intowhich the ignition key 1, serving as an immobilizer operation member, isinserted. The second indication portion is formed by impressing “Immobi”in the same manner as the first indication portion 11 of the ignitionkey 1 employed in the first embodiment. The dimensions of the two“Immobil” indication may be identical or similar. In FIG. 4, a key hole31 is provided in the end surface of the key cylinder 23.

The advantages of the second embodiment will now be described.

(A) In this embodiment, an impression similar to the first indicationportion 11 provided on the grip 3 of the ignition key 1 is provided onthe key receiving surface of the key cylinder 23. Thus, when theignition key 1 is inserted into the key cylinder 23, the ignition key 1and the key cylinder 23, which serves as an immobilizer operation memberreceiving device, can both be acknowledged as being relevant to theimmobilizer system.

(B) In addition, if an ignition key is used that is not part of theimmobilizer system, it can be confirmed that an immobilizer system isinstalled in the vehicle by looking at the second indication portion 30of the key cylinder 23.

The present invention may also be embodied in the further embodimentsdescribed below.

1) The holder 4 and the protector 5 of the above embodiments may be madeof other appropriate materials such as polyethylene (PE), polypropylene(PP), acrylonitrilebutadiene-styrene copolymer (ABS), or the like.

2) In addition to transponders, the above embodiments may be applied toan ignition key having a grip that incorporates a keyless transmitter,which constitutes a keyless system and transmits keyless identificationcodes.

The phrase “keyless system” refers to a system that locks or unlocksvehicle doors with a door locking mechanism when a keylessidentification code transmitted by the keyless transmitter and receivedby a keyless receiver, which is arranged in the vehicle, matches apredetermined keyless identification code.

3) A plasticizer may appropriately be added to the PVC, or the like, ofwhich the protector 5 is made, to apply rubber elasticity to the grip 3.This improves the feel of the grip 3.

4) In the above embodiments, the first indication portion uses letters.However, as shown in FIG. 5, for example, a symbol representing a keyand radio waves, may be impressed instead. FIGS. 6(a)-(d) showembodiments using other symbols. In FIG. 6(a), “E” is impressed as asymbol to indicate the inclusion of electronic components in the grip 3.FIG. 6(b) shows a capsule-like symbol, which is similar to the shape ofthe transponder 7, as the first indication portion 11. In FIG. 6(c), asymbol of a transistor, which represents electronic components, formsthe first indication portion 11. In FIG. 6(d), a symbol representing thetransmission of radio waves forms the first indication portion 11.

The first indication portion 11 may be formed on the surface of the keyplate 2, as shown in FIG. 6(e), instead of on the grip 3, as shown inFIGS. 6(a)-(d). The first indication portion 11 may also be formed onboth the key plate 1 and on the grip 3.

A first indication portion 11 representing the actuated state of theimmobilizer system may be impressed on the grip 11, as shown in FIG.6(f).

5) In each of the illustrated embodiments, the first indication portion11 is impressed on the surface of the grip 3 to indicate theincorporation of the immobilizer transmitter. However, a voicesynthesizing circuit may be incorporated in the grip instead. The switchactivation by the transmitting key transmits radio waves and activatesthe voice synthesizing circuit to output “words” stored in the voicesynthesizing circuit. Signals representing a message notifying theoperator that duplication is prohibited, such as “this key is animmobilizer key, duplication is prohibited” are then output tosubsequently generate a voice with a converting device such as a compactspeaker. In this case, the first indication portion corresponds to thevoice synthesizing circuit that notifies the operator of the employmentof the immobilizer system.

6) In the first embodiment, the voice synthesizing circuit may beincorporated in the control circuit 25 of the vehicle. When the key isinserted into the key cylinder 23 and turned to the starting positionand the input identification code does not match the storedidentification code, the control circuit 25 sends a command code to theengine controller 26 to prohibit starting of the engine. A voice commandsignal is also sent to the voice circuit to generate “words” stored inthe voice synthesizing circuit. Signals representing a message notifyingthe operator that the engine cannot be started due to the key, such as“this key is not the ignition key for the immobilizer system of thisvehicle” are then output to subsequently generate a voice with aconverting device such as a compact speaker. In this embodiment, a statein which the identification code is not received from the key isconsidered to be a state in which the identification codes do not match.

In this case, the voice synthesizing circuit and the speaker provided inthe control circuit 25 of the vehicle serve as a notification means. Thecontrol circuit 25 serves as a notification control means that outputscommand signals to the voice synthetic circuit when identification codesare not sent from the key or when the input identification code does notmatch the stored identification code.

7) In the above embodiments, the transponder 7 is a cylindrical glasstube that contains electronic components. However, a wedge typetransponder or a substrate type transponder may be used instead.

8) In the above embodiments, the transponder 7 is arranged at an angleof 45° relative to the longitudinal axis of the key plate 2. However,the arrangement is not limited to this angle and may be changedarbitrarily to other angles.

9) The above embodiments are applied to an ignition key incorporating atransponder, which does not require a battery and which serves as animmobilizer transmitter. However, a battery B and a transmitter 13,which serves as an immobilizer transmitter in lieu of the transponder 7and which transmit a predetermined identification code, may beincorporated in the grip 3. The battery B supplies the transmitter 13with electric power. In this case, as shown in FIG. 7, the battery B andthe transmitter 13 are electrically connected to each other by way of abutton switch 12, which is arranged on the grip 3. The button switch 12is pressed to activate the transmitter 13 and transmit theidentification code.

Regarding the embodiment of FIG. 1, a button switch may be arrangedbetween the capacitor and the IC. In this case, the button switch ispressed to activate the transmitter when charging of the capacitor iscompleted.

10) In the above embodiments, a transponder 7, which serves as animmobilizer transmitter, is incorporated in the grip 3 of the ignitionkey 1. However, an immobilizer transceiver may be incorporated in lieuof the transponder 7. In this case, the immobilizer system is providedwith an identification code transceiver, which is arranged in the keycylinder and which transmits an identification code. When an ignitionkey is inserted into the key cylinder, the identification codetransceiver is activated to transmit the identification code. Theimmobilizer transceiver of the ignition key then receives theidentification code and transmits a permission signal if the receivedidentification code matches the predetermined identification code. Whenthe key cylinder transceiver receives the permission signal, the enginecontrol computer permits the starting of the engine. If the permissionsignal is not received, starting of the engine is prohibited.

In this case, the immobilizer transceiver arranged in the ignition keyserves as the immobilizer receiver.

11) The above embodiments are applied to ignition keys. However, inaddition to ignition keys, the above embodiments may also be modifiedout by arranging an immobilizer transmitter, such as a transponder, on acard 15, or by arranging a receiver in a card having a first indicationportion 11. The letters “IMMOBI” are impressed or printed to serve asthe first indication portion 11. In FIG. 8, the diameter of thetransponder 7 is greater than the thickness of the card. Thus, a lobe 16is formed on the surface of the card.

12) In the second embodiment, the immobilizer operation member includesthe first indication portion 11. However, the second embodiment can beconstructed such that only the key cylinder 23 has a second indicationportion.

13) In the second embodiment, the immobilizer operation member receivingdevice of the vehicle is provided in the key cylinder 23. However, theimmobilizer operation member receiving device may be defined on memberslocated near the key cylinder. It is significant that the immobilizeroperation member receiving device be arranged at a location that allowsthe driver to acknowledge that an immobilizer system is installed in thevehicle.

14) In the second embodiment, the second indication portion is providedon the key cylinder 23. However, a third indication portion, which is asymbol or word indicating the installation of the immobilizer system,may be provided on the instrument panel, the door, the door handle, orother parts of the vehicle, as long as the third indication portion canbe acknowledged by the driver.

The following further summarizes the immobilizer and parts thereof.

In one embodiment (not illustrated) the embedded electronic componentkey has a grip including a voice synthesizing circuit, which serves as afirst indication portion, for generating a message output notifying that“duplication is prohibited”, a converting device for converting theoutput to a voice, and a switch for activating the voice synthesizingcircuit.

In this structure, a voice notifying that “duplication is prohibited” isgenerated by the key. In this case, the speaker in the above paragraph5) corresponds to the converting device.

As described above in detail, the immobilizer operation member informsthe user that the immobilizer operation member incorporates animmobilizer system element so that the user will handle the immobilizeroperation member with care. Furthermore, troubleshooting of the systemcan be carried out without delay.

The arrangement of the indication portion on the grip, where attentionis most paid, results in attention to the handling of the operationmember.

The third indication portion indicating the employment of theimmobilizer system leads to recognition of the installation of theimmobilizer system in the vehicle.

When both first and second indication portions are used, the immobilizeroperation member and the immobilizer operation member receiving deviceare recognized as both being relevant to the immobilizer system.

In the embodiment where the activator has a transceiver that sends acommand when the codes do not match notification control means outputs acommand to the notification means when the immobilizer identificationcodes do not match each other. The notification means then indicatesthat the immobilizer codes do not match based on the command. Thus, ifthe engine cannot be started, troubleshooting of the system is notdelayed.

What is claimed is:
 1. An immobilizer system for installation in avehicle to prevent unauthorized use of the vehicle, the immobilizersystem comprising: a receiver attached to the vehicle; a circuit in thevehicle for storing a first code, the circuit being linked with thereceiver; an operation member, which is independent and separable fromthe vehicle, wherein the operation member stores a second code, andwherein the operation member activates the circuit to perform averification process for verifying when the operation member is placedin a predetermined position with respect to the vehicle; a transmitteraccommodated in said operation member for transmitting a signal to thereceiver for communication with the receiver regarding a comparison ofthe second code stored in the operation member with the first codestored in the circuit, wherein operation of the vehicle is permittedonly when the first and second codes match; and an indication portionlocated on the surface of one of said operation member and the vehiclefor indicating the existence of the immobilizer system, wherein theindication portion is capable of being noticed by a vehicle operator. 2.The system of claim 1, wherein the indication portion comprises a firstindication portion located on the operation member, and a secondindication portion located on a surface of the vehicle that is visibleto the operator.
 3. The system of claim 2, wherein the operation memberis a key that is engagable with a key opening formed in the vehicle, andthe first indication portion is a symbol located on the key.
 4. Thesystem of claim 3, wherein the first and second indication portions aresymbols that are substantially the same.
 5. The system of claim 1,wherein the operation member is a key that is engagable with a keyopening formed in the vehicle, and the indication portion comprises afirst symbol located on the vehicle in close proximity to the keyopening.
 6. The system of claim 5, wherein the indication portionfurther comprises a second symbol located on the key.
 7. The system ofclaim 6, wherein the first and second indication symbols aresubstantially the same.
 8. The system of claim 1, wherein the operationmember is a key that is engagable with a key opening formed in thevehicle, and the indication portion is a symbol located on a grip of thekey.
 9. An immobilizer system for installation in a vehicle to preventunauthorized use of the vehicle, the immobilizer system comprising: areceiver attached to the vehicle; a circuit connected to the receiverand including a storage device in the vehicle for storing a first code,the circuit being linked with the receiver; an operation member to behandled by a vehicle operator, wherein the operation member isindependent and separable from the vehicle, wherein the operation memberstores a second code, and wherein the operation member activates thecircuit; a transmitter accommodated in said operation member fortransmitting a signal to the receiver, wherein operation of the vehicleis permitted only when the transmitted signal indicates that the firstcode stored in the storage device matches the second code stored in theoperation member; and a symbol located on the surface of one of saidoperation member and the vehicle for indicating the existence of theimmobilizer system, wherein the symbol is in a position such that thesymbol is likely to be noticed by a vehicle operator when the vehicleoperator uses the operation member.
 10. The system of claim 9, whereinthe symbol comprises a first symbol located on the operation member, anda second symbol located on a surface of the vehicle that is visible tothe operator.
 11. The system of claim 10, wherein the operation memberis a key that is engagable with a key opening formed in the vehicle. 12.The system of claim 11, wherein the first and second symbols aresubstantially the same.
 13. The system of claim 9, wherein the operationmember is a key that is engagable with an opening formed in the vehicle,and the symbol comprises a first symbol located on the vehicle in closeproximity to the opening.
 14. The system of claim 13, wherein the symbolfurther comprises a second symbol located on the key.
 15. The system ofclaim 14, wherein the first and second symbols are substantially thesame.
 16. An immobilizer system for installation in a vehicle to preventunauthorized use of the vehicle, the immobilizer system comprising: areceiver attached to the vehicle; a circuit in the vehicle for storing afirst code, the circuit being connected with the receiver forcommunicating with the receiver; an operation member to be handled by avehicle operator and to be engaged with the vehicle prior to operationof the vehicle, wherein the operation member is independent andseparable from the vehicle, wherein the operation member stores a secondcode, and wherein the operation member activates the circuit to performa verification process for verifying whether the operation member isauthorized for use with the vehicle when the operation member is engagedwith the vehicle; a transmitter and an antenna, both embedded in theoperation member, for transmitting a signal to the receiver forcommunication with the receiver regarding a comparison of the secondcode stored in the operation member with the first code stored in thecircuit, wherein operation of the vehicle is permitted only when thefirst and second codes match; and a readily noticeable symbol formed onthe surface of one of said operation member and the vehicle forindicating the existence of the immobilizer system to a person.
 17. Thesystem according to claim 16, wherein the operation member is a key, andthe symbol is formed on a grip of the key.
 18. The system according toclaim 17, wherein a second symbol that is substantially identical to thesymbol formed on the key is formed on the vehicle in a location that isreadily noticeable.
 19. The system according to claim 16, wherein theoperation member is a key, and the vehicle includes a key opening forreceiving the key, and wherein the symbol is formed on the vehicle inclose proximity to the key opening.